Exchange 2007 Event ID 32768


  • I am running Exchange 2007 SP1 with OCS 2007 R2 and when sending Voicemail to the exchange server I keep finding the following error in the logs.


    Event Type: Warning
    Event Source: Microsoft Exchange Speech Engine
    Event Category: Telephony Application Host
    Event ID: 32768
    Date:  2/18/2009
    Time:  10:25:45 PM
    User:  N/A
    Computer: Exchange
    The Telephony Manager declined a call with Call Id 'fd64b2e5ef8e4cd38b443b2400ac505e' for the following reason in component telephony session: 'The media description received from the remote SIP peer has an invalid content type 'multipart/alternative'.'. 
    Further trace information for support personnel follows:
    Microsoft.SpeechServer.Core.InvalidMediaException: The media description received from the remote SIP peer has an invalid content type 'multipart/alternative'.
       at Microsoft.SpeechServer.Core.MediaNegotiation..ctor(LoggingContext loggingContext, ContentDescription rtcRemoteMediaOffer)
       at Microsoft.SpeechServer.Core.TelephonySessionInbound.CreateMediaNegotiation(ContentDescription rtcMediaDescription, SessionInfo sessionInfo, CallInfo callInfo, IPEndPoint sipPeerEndpoint)
       at Microsoft.SpeechServer.Core.TelephonySessionInbound.Initialize(SessionInfo sessionInfo, SessionReceivedEventArgs e, CallInfo callInfo, EventSerializer serializer, SpeechSession speechSession, Boolean isTlsConnection)
       at Microsoft.SpeechServer.Core.TelephonySessionInbound..ctor(SessionInfo sessionInfo, SessionReceivedEventArgs e, CallInfo callInfo)
       at Microsoft.SpeechServer.Core.TelephonyManager.CreateSession(Int32 inviteReceivedTickCount, SessionReceivedEventArgs e)
       at Microsoft.SpeechServer.Core.TelephonyManager.SignalingSessionReceived(Object sender, SessionReceivedEventArgs e)

    For more information, see Help and Support Center at

    However I am recieving and sending voicemails with out issues.  Can anyone steer me in the right direction?

    Thursday, February 19, 2009 4:44 AM

All replies

  • OCS R2 sends two alternatives of SDP encapsuled in MIME to support two different ICE versions.
    Obviously Exchange UM is not prepared for that but still can parse and use SDP successfully.

    This will be updated in Exchange for sure.

    Johann Deutinger | MCTS Exchange 2007 / OCS 2007
    Thursday, February 19, 2009 10:50 AM
  • I am getting the same error, however vmail is NOT picking up.  Any thoughts on where to start troubleshooting?

    Monday, April 27, 2009 4:23 PM
  • I also have the same error.  External calls are being answered by the UM service and saved as Voicemails.

    Internals calls from the MOC client direct to voicemail is being refused.  Also - no voicemails or missed calls notifications are being delivered (1082 errors)

    Worked perfectly until this morning.

    Wednesday, May 20, 2009 6:10 PM
  • Same here...    The error is logged, and also our Exchange AutoAttendants (which we use a LOT) fail to answer.  Restarting the UM service doesn't help.  Restarting the speech engine fails...
    Wednesday, June 17, 2009 1:53 PM
  • This error is a red herring... noise, if you will.  If you're having other problems, it's not likely due to this specific 32768 error.


    Sunday, June 21, 2009 9:15 PM
  • Yes, I have met the same problem in Lab OCS 2007 R2 interworking with Exchange 2007.
    First ,in my lab ,there is ceritifcate issue on Exchange 2007 and I managed to install certificate on Exchange and Re-Start UM service
    Second, I found this same problem ,for Exchange 2007 is unable to recognize the SDP multipart/alternative from INVITE of OCS R2 Frond End and UM response 500 (internal server error), thus OCS R2 will NOT send out the INVITE without SDP multipart/alernative.

    Third, I have to reboot the Exchange 2007 server, then this time When Exchange UM receiving SDP multipart/alternative ,it will send reponse 415(Unsupported Media ),
    Then OCS receive response 415 and re-send INVITE without SDP multipart/alternative and UM response 200 OK,then it works.

    Friday, December 18, 2009 9:54 AM